(define (every? pred lst)
    (cond 
        ((null? lst) #t)
        ((pred (car lst)) (every? pred (cdr lst)))
        (else #f)
    )
)

(display 
    (every? number? `(a b c 3 e))
)

(display 
    (every? number? `(1 2 3 5 4))
)
